BOULDER - Boulder's new ban on so-called assault weapons is already being challenged in court.

The ban - Ordinance 8245 - passed unanimously by the City of Boulder's nine councilors doesn't just ban "assault" weapons in the city, but also bump stocks, large magazines and raises the age to purchase a gun from 18 to 21.

A lawsuit, filed on Thursday, claims the ordinance "violate[s] multiple provisions of the U.S. Constitution including Article VI, the First Amendment, the Second Amendment, the Fifth Amendment and the Fourteenth Amendment."

The lawsuit comes from a Boulder resident named Jon Caldara and the Boulder Rifle Club. Caldara serves as the president of the Independence Institute, the largest recipient of NRA funds in Colorado.

It also states that several provisions of the State Constitution and State statutes were violated when Boulder City Council approved the new law.

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Some of the reasoning cited in the lawsuit is that current owners of the weapons have to register with the government - something the plaintiffs see as a First Amendment violation - and that the ordinance requires gun owners to give up, turn in or break the banned weapons without compensation - a Fifth Amendment problem, according to the lawsuit.

The plaintiffs also argue the ban would infringe upon two parts of the 14th Amendment.

First, the Privilege and Immunities Clause, which says that no state can make a law infringing upon citizens' privileges. Caldara and company argue in the suit that gun ownership isn't just a right - it's a privilege, and therefore this law directly contradicts that part of the 14th Amendment.

Second, the Equal Protection Clause of the amendment, which says no state can deny any person equal protection under laws. Caldara, in his suit, argues that by changing the age of gun ownership to 21 from 18, that denies 18 - 20 year olds equal protection under the law, since people of those ages can vote, join the military, smoke, enter into a contract and do other things.

This is in addition to the more obvious argument about Second Amendment rights to bear arms that is mentioned heavily throughout the text of the suit.

The lawsuit states that since the ordinance would require gun owners to give up, turn in or break the banned weapons without compensation.

Also brought up in the suit is the Colorado Constitution, which parrots many of the same rights as the U.S. Constitution, including the right to bear arms.

The plaintiffs in the suit want a trial by jury, hoping to have it ruled that the ban is unconstitutional, and a judgment from the court reaffirming their rights to buy firearms, have large magazines and let 18 - 20 year olds buy firearms.

They'd also like the costs, expenses, attorney fees related to this case covered and any other judgments felt "just and equitable" by the court.

Neither the City of Boulder nor Boulder Police would comment on the lawsuit Thursday.

The full 60-page suit is reproduced below: